1. Field of the Invention
The present invention is broadly concerned with low moisture, stable food products and a method for making these products. More particularly, the food products include a component selected from the group consisting of snack chips, seasonings, fruits, cheeses, and cookie materials wherein the average particle size of the refined food product is from about 0.0006-0.0012 inches (15-31 microns), and the total moisture content of the product is less than about 5% by weight based on the total weight of the product. The processes by which the products are made preferably include subjecting a quantity of starting ingredients to two distinct steps to reduce the average particle size. Preferably, particle size reduction is accomplished via a refiner system which comprises a two roll pre-refiner that reduces the average particle size to less than about 0.0090 inches (229 microns), and a five roll refiner that reduces the average particle size to about 0.0006-0.0012 inches (15-31 microns).
2. Description of the Prior Art
There are numerous products in the food industry which are useful for enhancing common food products. For example, cookie dough chunks can be added to ice cream, fruit chunks can be added to cereal, and cheese pieces can be baked into breads. However, the products currently available have high moisture and will spoil quickly if not properly stored. For example, most cheese products contain water as an added ingredient. Water, however, adversely affects the shelf stability of the product, thus requiring it to be aseptically packaged or stored under-refrigerated conditions. While cheeses with low moisture contents have been attempted, these products generally lack the consistency and texture which make it appealing to consumers.
Products composed of fats, sugars, dry dairy powders, flavors, colors, and other dry ingredients can be manufactured which are fruit-flavored and fruit-colored. The advantage of these fruit-flavored products is that they are low in moisture and therefore highly shelf-stable, capable of being stored for as long as six months at room temperatures without fear of microbial deterioration. However, these fruit-flavored products do not contain significant quantities of real fruit. Incorporating real fruits directly into fat-based masses at levels greater than 3% causes processing and stability problems due to the high moisture content of fruit. In an attempt to overcome these problems, partially dehydrated fruits are sometimes dried in combination with non-fruit ingredients to improve flowability and prevent clumping. Even these partially dehydrated fruit products contain significant levels of moisture however, and therefore are only marginally better than fresh fruit products in terms of stability.
Cookie dough chunks as used in ice cream and other frozen desserts typically contain raw wheat flour, sugar, water, fat, and other ingredients. However, these cookie dough chunks suffer from the same problems as the cheese and fruit products discussed above. They contain as much as 40% moisture and have a high water activity (approximately 0.9 at 20.degree. C.), thus they must be kept refrigerated or frozen in order to prevent spoiling.
Chocolate is usually produced by a particle size reduction method known as five roll refining. A five roll refiner consists of five rolls, four of which sit directly on top of each other, wherein the first two rolls have an adjustable gap (or roll gap) which allows a thin film of material to move between the two rolls. Each of the succeeding rolls have non-adjustable gaps between them, further allowing a thin film of edible material to move between each of the rolls. Each roll is temperature and pressure controlled and milled so that the particles generated at all points are of substantially equal size. With passage between each of the rolls, the film becomes thinner and the average particle size becomes smaller. In order to enhance the control over particle size, a system of two or five roll refiners can be utilized to pre-refine the material prior to refining. While other suitable methods of particle size reduction exist (such as grinders, hammermills, ball mills, and stone mills), the roll refining system has been the predominant method for manufacturing chocolate.
U.S. Pat. No. 3,843,808 to Ziccarelli is directed towards a process for forming shelf-stable, cheese-flavored products by finely dispersing fat particles and enrobing those fat particles in an enrobing agent to prevent the coalescence of the fat particles. However, the cheese products formed in the Ziccarelli patent have a very coarse, grainy texture which is unappealing in many applications. Furthermore, large quantities of cheese or cheese flavoring is required in the Ziccarelli products in order to obtain a sufficiently strong cheese flavor, resulting in increased product cost. This is due to the fact that the cheese particles are too large and are not uniformly distributed throughout the product.
There is a need for snack chip, cheese, fruit, cookie dough, and seasoned products, and a process for making these products, having a low moisture content and thus being resistant to microbial deterioration. The products must be capable of being stored for long periods of time at room temperature. Furthermore, these products must have a texture and flavor similar to cheese, fruit, or cookie dough products having high levels of moisture. The snack chip flavored products and seasoned products should have a strong, uniformly distributed flavor. Finally, the process for producing these food products must be workable on presently available equipment that is capable of substantially reducing the average particle size of the products thus maintaining a natural texture.